Yarn handling apparatus

ABSTRACT

A device for temporarily storing yarn for immediate use by a yarn consuming textile apparatus, such as a winder, a knitting machine, or for the filling thread of a shuttleless loom. The device includes a yarn collecting drum on which yarn from a supply source is wound temporarily and then removed under a controlled, uniform tension. The device eliminates the wide variations in yarn tension which occur when a yarn is delivered from a source, such as a cone or a package, and permits the yarn to feed to a textile machine at a substantially constant tension.

United States Patent 1 Lawson Dee.4,1973

[ YARN HANDLING APPARATUS [75] Inventor: John B. Lawson, Providence, RI.

[73] Assignee: Lawson-Hemphill, Inc., Central Falls, R.l.

[22] Filed: Apr. 5, 1972 [21] Appl. No.: 241,207

[52] US. Cl. 242/47.01,.57/58.3, 57/58.49, 57/67, 66/132, 242/47.l2,242/47.13

[51] Int. Cl. B65h 51/20 [58] Field of Search 242/47.01, 47.04,242/47.05, 47.08, 47.09, 47.12, 47.13;

[56] References Cited UNITED STATES PATENTS 1,960,743 5/1934 Junkers242/47.09 2,388,591 11/1945 Andreas.... 242/47.13

2,435,430 2/1948 Ewing 242 47.13

2,439,903 4/ 1948 O'Connell, Jr 242/47.13 2,469,767 5/1949 Hellbach2,936,877 5/ 1960 Adams et a1 242/47.09 3,225,446 12/1965 Sarfati et al.242/47.01 X 3,490,710 l/ 1970 Muhlhausler 242/47.01 3,672,590 6/1972Rosen 242/47. 12 3,713,307 1/1973 Muhlhausler 242/47.01 X 3,720,384 3/1973 Rosen 242/47.01

Primary ExaminerStanley N. Gilreath Attorney-Henry N. Paul, Jr. et al.

[57] ABSTRACT A device for temporarily storing yarn for immediate use bya yarn consuming textile apparatus, such as a winder, a knittingmachine, or for the filling thread of a shuttleless loom. The deviceincludes a yarn collecting drum on which yarn from a supply source iswound temporarily and then removed under a controlled, uniform tension.The device eliminates the wide variations in yam tension which occurwhen a yarn is delivered from a source, such as a cone or a package, andpermits the yarn to feed to a textile machine at a substantiallyconstant tension.

26 Claims, 24 Drawing Figures PATENTED U 3,776,480

SHEET OlUF 11 PATENTEDUEE 41m 3,776,480

' sum UEUF 11 PATENTED 75 sum 3 or 11 FIG.6

FIG. 7

PATENTED 4W5 SHEET UHUF 11 FIG.8

PATENTED DEC 41973 SHEET USBF 11 PATENTED 41975 3.776.480

SHEET mm H PATENTEUUEB 41m SHEET 080! 11 PATENTEU 3,776,480

sum mar 11 PATENTED 4 7 sum nor 11' YARN HANDLING APPARATUSCROSS-REFERENCE TO RELATED APPLICATION This application is acontinuation-in-part of my pending patent application Ser. No. 138,749,filed Apr. 29, 1971 and entitled Yarn Tension Equalizer, now abandoned,and is a continuation of my pending patent application Ser. No. 230,257,filed Feb. 29, 1972 and entitled YARN HANDLING APPARATUS, now abandoned.I

SUMMARY OF THE INVENTION The primary object of this invention is toprovide a new and improved yarn handling apparatus by which yarn may bewithdrawn from a source of supply, and so handled that wide variationsin tension on the yarn are eliminated and the yarn then permitted toadvance under a selected uniform tension to a suitable textile machinefor further processing.

To achieve this disideratum, the invention, in its preferred form,comprises an automatic yarn tension equalizer, i.e. yarn storage feederhaving a drum about which yarn is wound helically to form a plurality ofyarn turns, to provide a temporary yarn store, and from which the yarnis removed in a generally axial direction at one end. A yarn guidedirects yarn to the drum, and means are provided for rotating the guideand drum relative to each other, whereby the yarn is deliveredtangentially to the drum. The drum preferably includes means foradvancing the yarn turns thereon axially toward the yam discharge end ofthe drum. A pneumatic system, under control of a yarn sensing means, isprovided for imparting suitably controlled relatively rotationalmovement between the yarn, guide and the drum, to ensure that asufiicient store of yarn is wound on the drum at all times to meet thedemands of the textile machine to which the yarn is being delivered.

DESCRIPTION OF THE VIEWS OF THE DRAWING FIG. 1 is a fragmentary view inperspective of a preferred embodiment of this invention.

FIG. 2 is a schematic front elevation of a circular knitting machineutilizing a plurality of devices of the type illustrated in FIG. 1.

FIG. 3 is a schematic illustration in top plan showing a preferred drivemeans for the devices of this invention illustrated in FIG. 2.

FIG. 4 is an enlarged, partially sectional view in side elevationindicated generally by the arrows 4-4 of FIG. 1.

FIG. 5 is a fragmentary view in perspective of the stop motion of thedevice of FIG. 1.

FIG. 6 is a fragmentary, partially sectional view in side elevation ofthe device shown in FIG. 1.

FIG. 7 is a cross section indicated by the arrows 7-7 of FIG. 6.

FIG. 8 is a fragmentary, partially sectional view in side elevation of amodification of the device shown in FIG. 1.

FIG. 9 is a cross section indicated by the arrows 9-9 of FIG. 8.

FIG. 10 is a fragmentary, partially sectional view in side elevation ofa second modification of the device shown in FIG. 1.

FIG. 11 is a cross section indicated by the arrows 11-11 of FIG. 10.

FIG. 12 is a fragmentary view in perspective of a third modification ofthis invention.

FIG. 13 is an enlarged fragmentary, generally sectional view in sideelevation indicated by the arrows 13-13 of FIGS. 12 and14.

FIG. 14 is a cross section indicated by the arrows 14-14 of FIG. 13.

FIG. 15 is a cross section indicated by the arrows 15-15 of FIG. 13.

FIG. 16 is a cross section indicated by the arrows 16-16 of FIG. 13.

FIG. 17 is a fragmentary view in section indicated by the arrows 17-17of FIG. 13.

FIGS. 18 and 19 illustrate modifications of the pneumatic systemutilized in this invention.

FIG. 20 is a fragmentary, inverted schematic view in section of atwo-ply cord former incorporating the novel detent of this invention.

FIG. 21 is a fragmentary, inverted schematic view in section of atwo-for-one twister incorporating the novel detent of this invention.

FIG. 22 is a fragmentary, inverted schematic view in section of amodified twister incorporating the novel detent of this invention.

FIGS. 23 and 24 are fragmentary, schematic views of yet anothermodification of this invention.

DETAILED DESCRIPTION OF THE INVENTION In FIG. 1, there is shown apreferred form of yarn tension equalizer 20 embodying this invention. Aplurality of such devices 20 may be mounted on a single textile machine,such as the multifeed circular knitting machine 142 shown in FIG. 2, fordelivering yarn 22 thereto from a plurality of yarn cones or yarnpackages 144. The several yarn tension equalizers 20 shown in FIG. 2 maybe driven by a single endless belt 90, as shown in FIG. 3. The drivesystem, in addition to belt 90, may include an electric motor 146driving a pulley 147, and a plurality of retractable idler pulleys 108.Belt is entrained about the pulleys 108 and 147.

Referring now to FIGS. 1 and 4-7, the device 20 includes a stationarysupport 24 adapted to be secured, in a suitable manner and location, to,or adjacent to, the textile machine or apparatus to which the yarn 22 isto be delivered. Affixed to the upper end of support 24, by suitablemeans such as bolts 25 (FIG. 4), is a cup-shaped member 40 having acylindrical cavity 44 (FIG. 4) formed in the bottom thereof. Cavity 44is sealed at the top by a flexible diaphram 46, which is secured inplace by a retaining ring 48. A plurality of threaded bolts 49 securering 48 to the rim of the cavity The floor of the cavity 44 is formedwith an aperture through which protrudes the upper end of a verticalstud shaft 50. The protruding upper end of shaft 50 is securedinternally of cavity 44 by a nut 54 in the cavity. The engagement ofshaft 50 within the floor of the cavity 44and the nut 54 is air tight.Cavity 44, as will be explained presently, comprises an air chamber.

An axial bore 52 extends the entire length of shaft 50, and has itsupper end in open communication with the cavity 44. A ball valve 64 issecured to the distal or lower end of shaft 50, and has a verticalpassageway disposed between bore 52 and the ambient atmosphere. Thepassageway comprises an upper, constricted portion or orifice 66 incommunication with bore 52, and a lower, larger portion 67 whichcontains a pair of steel balls.

Valve 64 is closed by a lever 116 pivoted at 117 and having its distalend 120 formed into a reverse bend. Lever 116 is urged into valveclosing'position by leaf spring 122. Lever 116 mounts and adjustmentscrew 124 having a reduced, axial extension 125 adapted to engage withinthe lower portion 67 of the passageway of ball valve 64. When spring 122is permitted to pivot lever 116 upwardly into valve closing position, asshown in FIG. 4, extension 125 engages within the passageway to forcethe balls therein to their uppermost position to seal orifice 66 andclose the valve.

The cavity or air chamber 44 is connected to a source of compressed air(not shown) by means of a bore 58 in member 40 and a tube 60, the latterengaging in an airtight fit within bore 58. Disposed in the bore 58,between the air chamber 44 and the end of tube 60, is a plug providedwith a small, axial orifice 62, through which compressed air passes fromtube 60 to air chamber 44. The cross sectional area of orifice 62 isconsiderably smaller than the cross sectional area of the orifice 66 inball valve 64. Preferably, the cross sectional area of orifice 66 is atleast three times larger than that of the orifice 62.

Thus, the yarn tension equalizer illustrated in FIG. 1 incorporates apneumatic system comprising a source of compressed air (not shown), anexpansible air chamber 44 connected to said source, an axial bore 52connecting the air chamber to the ambient atmosphere, a valve 64 foropening and closing the air chamber to the atmosphere and aspring-biased lever 116 for opening and closing the valve.

Stud shaft 50 supports a pair of vertically spaced ball bearings 76 onwhich is rotatably mounted a yarn collecting drum 26. The drum 26includes a rotatable core 78 affixed to the roller bearings 76, a drivering 86 affixed to the upper end of the core and a hollow housing 94affixed to the lower end 'of the core. The ring 86 has a dependent,outwardly inclined skirt portion 88, the outer surface of which isadapted to engage frictionally the drive belt 90, to impart rotation tothe drum 26. The housing 94 supports an annular rubrail 92 for the yarn22, as it discharges from the drum 26.

The core 78 of drum 26 is formed with a plurality of vertical,peripherally spaced slots 80 in each of which is mounted a slidable flatbar or slat 82. The bars 82 are formed with inner, vertical extensionsat their top and bottom edges for slidable engagement, respectively,within annular-cam tracks in vertically spaced stationary earns 68 and70 (FIGS; 4,6). Thecarns 6 8'and 70 are keyed to stud shaft 50, and areprovided, respectively with opposed, complementary cam rings 72 and 73.The cam rings 72 and 73 are formed with complemental, undulating orsinuous flat surfaces which snuggly engage the upper and lower edges,respectively, of the slats 82, thereby imparting to them a continuousup-and-down motion, as indicated by the vertical arrows in FIG. 6, whendrum 26 rotates.

As will best be seen from FIG. 7, the earns 68 and 70 are mountedeccentrically of stud shaft 50. They are tal back-and-forth movement isimparted to the slats 82 by the bearings 74, as indicated by thehorizontal arrows of FIG. 6. Thus, both horizontal and verticalreciprocatory movements are imparted to the slats 82 disposed in slots80. The slats or bars 82 move in a cyclic motion, which is upwardly andinwardly of the slots 80 and then downwardly and outwardly thereof, asdrum 26 rotates. The arrangement and dismensioning of the parts is suchthat when slats 82 are in their most advanced position, their outervertical edges protrude slightly beyond the periphery of drum core 78,and when in their most retracted position, are withdrawn fully intoslots 80 (see FIG. 6).

Mounted on the drum core 78, for rotation therewith, is a verticallydisposed yarn sensing finger 114. The upper end of finger 114 is pivotedat 113 to core 78, while its lower portion extends through a slot inhousing 94 and terminates therein in the form of an upwardly curved end115. The latter is adapted to engage the distal end 120 of lever 116.

The upper portion of finger 114 is disposed inwardly of the periphery ofcore 78, while its lower portion is spaced outwardly from saidperiphery, the two portions provided with opposed axial extensions,on'each of which is mounted a ball bearing 74 (FIGS. 4,6). The

being joined by a downwardly, outwardly inclined medial portion 114'.Finger 114 is urged outwardly of the drum 26, about pivot 113, by aspring 118 mounted in core 78. When finger 114 is in its outermostposition, its distal end disengages from the distal end 120 of lever116, whereby the latter is pivoted upwardly by spring 122 to close ballvalve 64.

Affixed to and depending from the bottom of the housing 94 is averticalpin 132, to the lower end of which is affixed a shield 138. The shield138 has an inverted, frusto-conical configuration, and supports,telescopically of pin 132, a tube 133 having a vertical slot 135 formedtherein. Mounted rotatably on pin 132, in a narrow space between thebottom of housing 94 and the top of shield 138, is a flyer 32 composedof a wire element 126 affixed in a clamp 128. Flyer 32 is rotatableabout pin 132 against a selective frictional force imposed on clamp 128by spring 130 disposed about pin 132. A vertically slidable knurled ring134, secureable on pin 132 by a set screw 136, is utilized to varyselectively the frictional force exerted by the spring on the clamp 128,against'which the flyer 32 is rotatable.

The drum 26 is driven intermittently by belt 90, utilizing a driving andbraking means indicated generally by reference numeral 28 (FIGS. 1, 4).the driving and braking means 28 includes a vertically movable piston 98mounted slidably within air chamber 44 and its superimposed ring 48.Diaphram 46 is interposed between the bottom of the piston 98 and theinterior of the air chamber 44, but because of its elastic quality,permits the piston to slide vertically within the air chamber 44. Formedin the top of piston 98 is a slot 99, which is aligned with a slot 42(FIG. 1) in the distal wall portion of the cup-shaped member 40. A lever100 is pivoted at approximate its mid-point in slot 42 about a pin 101.The inner end of lever 100 is connected pivotally to pin 96 within slot99 of piston 98. The outer end of lever 100 is connected pivotally to avertical link 102 which, at its lower end, mounts a vertical stud shaft103 for rotatable idler pulley 108, about which belt 90 passes (FIGS.3,4).

Pivoted to the lower end of link 102 is a lever 104 which forms into atrifurcated component having elements 104', 104" and 104""(FIG. 1). Theelements or extensions 104' and 104" of lever 104, at their respectivedistal ends, each support brake shoes 106 adapted to engage frictionallythe top surface of drive ring 86 and thereby stop the rotation of drum26 when drive belt 90 is retracted. The outer cylindrical wall of member40 is undercut to accommodate the distal ends of elements 104 and 104"and their respective brake shoes 106.

Element or extension 104 of lever 104 is pivoted at its inner end withinthe bottom portion of slot 42 of member 40 by means of a pin 105 (FIG.4). The inner end of element 104" is formed with a vertically upstandingportion 107. Lever 100 is provided with a depending portion 109 spacedfrom the upstanding portion 107 of element 104". The portions 107 and109 are provided with opposing, cylindrical recesses or openings inwhich is retained a coil spring 112. The function of spring 112 is tourge the lever mechanism 100, 102, 104 of linkage means 28 in agenerally clockwise direction, to retract idler pulley 108 and drivebelt 90 away from the drive ring 86. It also urges the linkage means 28into drum braking position while, at the same time, urging piston 98downward into air chamber 44.

The yarn tension equalizer is made ready for use by passing yam 22through upper yarn guide 36 in support 24, under the sensing finger 140of the stop motion 34, around the periphery of drum 26 a plurality ofturns, thence over rub rail 92, under flyer 32 and through the loweryarn guide 38 on support 24 for delivery to the yarn consumingapparatus. As the number of yarn turns on the drum increase and advancedownwardly thereof, they bear upon the exposed portion of yarn sensingfinger 114, and force it, against spring 118, to pivot inwardly of thedrum. As a result, the curved distal end of finger 114 slides againstthe reverse bent distal end 120 of lever 116, forcing the same to pivotdownwardly, against the force of spring 122, to open ball valve 64.Compressed air now passes through tube 60, bore 58, orifice 62, airchamber 44, bore 52 and valve 64 to the atmosphere. By reason of spring112, the pulley 108 and drive belt 90 are retracted from the drive ring86, and piston 98 is retracted into the recess of air chamber 44.

With the device thus prepared, motor 146 is started to activate drivebelt 90. The yarn consuming apparatus then is started, and begins todraw yarn 22 from the drum 26. As the number of yarn turns on the drum26 are reduced, yarn sensing finter l14is caused to pivot outwardly byspring 118, thereby permittinglever 116 to pivot upwardly to close valve64. As a result, compressed air no longer escapes from the air chamber44, and the air pressure increases therein, to raise piston 98 againstthe force of spring 112. Movement of piston 98 imparts a generallycounter-clockwise movement to the driving and braking linkage 28, toadvance pulley 108 toward drum 26 and bring drive belt 90 into contactwith drive ring 86 (FIG. 4). As a result, rotation is imparted to drum26 to draw a fresh supply of yarn 22 from the yarn source, and wrap ithelically about the drum 26.

As the drum 26 rotates, the slats 82 in slots 80 move outwardly anddownwardly and then upwardly and inwardly to advance the yarn turns onthe drum 26 axially toward the draw-off end of the drum. The slats 82serve asa yarn advancing means, to ensure that the plural yarn turns onthe drum do not overlap while they are stored on it.

When sufficient yarn turns again have been wound on the drum 26, theyarn sensing means 1 14 again is depressed by the yam, so that itsdistal end engages lever 116 to open the valve 64. Once again, thecompressed air escapes to the atmosphere through valve 64, to reduce airpressure in air chamber 44. Piston 98 then retracts into the chamber 44,under the influence of spring 112, while the drive belt 90 once again isretracted from the drive ring 86. Simultaneously, the brake shoes 106are brought into contact with drive ring 86 to stop rotation of drum 26.

Thus, in response to the amount of air pressure in chamber 44,intermittent rotation is imparted to drum 26 by drive belt 90, toprovide at all times a temporary yarn store for the immediate use of ayarn consuming apparatus, such as a knitting machine. Spring 118 for theyarn sensing finger 114 is designed to permit the finger to pivotinwardly, to open valve 64, after a predetermined maximum number of yarnturns are on the drum 26 and, likewise, to cause finter 114 to pivotoutwardly after the number of yarn turns on the drum have been reducedto a pre-determined minimum. The selection of the minimum and maximumnumber of yarn turns to accomplish this is a matter of choice, butshould be sufficient to ensure that there is an ample supply of yarn atall times on the drum 26 to meet the demands of the yarn consumingapparatus.

The yarn passing through guide 36 is wrapped tangentially about the drum26, and is withdrawn therefrom'through guide 38 in a generally axialdirection. A uniform, pre-deterrnined yarn tension is imposed on theyarn 22, as it advances to guide 38, by the flyer 32 under the controlof spring 130.

In the modification shown in FIGS. 8 and 9, the core of rotatable drum26' comprises a plurality of upright, circularly arranged, rotatablerollers 148 about which the yarn is wrapped. Rollers 148 have axes ofrotation offset a few degrees from the vertical, in the direction ofdrum rotation (FIG. 9), to ensure that the yarn turns are advanceddownward, to the discharge end of the drum 26. Rollers 148, at theirupper ends, are journaled in the drive ring 86, and at their lower endsare journaled in an annular plate 149 mounted on top of the housing 94.

A sun gear 150 is affixed to the lower portion of stud shaft 50, abovevalve 64. Affixed to each of the rollers 148, at the bottom thereof, forrotation therewith, is a gear 153, adjacent pairs of which mesh with asingle idler gear 152. The three idler gears 152 also mesh with sun gear150. When drive belt 90 is brought into driving engagement with drivering 86, to rotate drum 26', the interengagement of gears 150, 152 and153 causes the rollers 148 to rotate in a direction opposite to thedirection of rotation of drum 26. The arrangement causes the plural yarnturns wrapped about the several rollers 148 to advance axially downwardof the drum 26', .to the yarn discharge end of the drum. Except as justdescribed, the yarn tension equalizer of FIGS. 8 and 9 is substantiallyidentical in structure and operation to the device of FIG. 1.

In the modification of FIGS. 10 and 11, the core of the rotatable drum26" is composed of a plurality of vertical, circularly arranged endlessbelts 154 about which the yarn 22 is wrapped. The belts 154 are similarin purpose and structure to the endless belts illustrated and describedin a A. H. Junkers U.S. Pats. Nos. 1,851,252 and 1,960,743. The belts154 are supported on rotatable pulleys and are driven at a constant,relatively slow rate of speed, with the outermost portions advanciangdownwardly, to thereby uniformly advance the yarn turns axially towardthe yarn discharge end of the drum 26". The upper pulleys 155 of thebelts 154 are formed with spaced flanges 156 comprising worm gearsmeshing with a stationary worm 157 affixed to shaft 50. Thus, as drum26" rotates, the intermeshing of worm gears 156 with the stationary worm157 drives the belts 154. Except for the substitution of the endlessbelts 154 for the drum core 78, the device of FIGS. 10 and 11 issubstantially identical to the yarn tension equalizer illustrated inFIG. 1.

If desired, the yarn tension equalizer of this invention may be readilyconverted to a positive yarn feeding device. As illustrated in FIG. 4,to accomplish this, a mechanism such as toggle linkage 160 may bemounted pivotally on support 24, immediately below an extension 161 oflever 100. The toggle is provided with a protrubance 162 adapted toengage into a complementally formed notch 163 in the underside of leverextension 161. When the toggle is raised, to engage protrubance 162 intonotch 163, the linkage means is caused to shift in a generallycounter-clockwise direction to bring drive belt 90 into driving contactwith ring 86. The force of spring 112 serves to retain protrubance 162in engagement with notch 163, and hence retains the driving contactbetween belt 90 and ring 86 to impart continuous rotation to drum 26.

To complete the conversion of device to a positive yarn feeding device,the yarn must be arranged to be discharged tangentially from the drum26, rather than axially thereof. To provide for this, a yarn guide 165is mounted on support 24 opposite from the lower portion of drum 26, sothat the yarn passes from the periphery of the drum to guide 165 in amore or less horizontal direction, and thence proceeds downwardly to andthrough yarn guide 38, as indicated by the shadow line of FIG. 4.

FIGS. 12-17 illustrate a modified yarn tension equalizer 220 in whichthe yarn collecting drum 226 is stationary and the yarn guide 236 isrevolvable about the drum. In this embodiment (FIG. 12), rotatable yarnguide 236 wraps the yarn 22 tangentially around the drum 226. The pluralyarn turns are advanced axially of the drum to the draw-off end thereofby yarn advancing slats 282, and then are discharged axially of the drumthrough the stationary yarn guide 238. The flyer is omitted from thismodification, so that the yarn passes directly from drum 226 over rubrail 292 tothe yarn guide 238. Stationary support 224 mounts the deviceto, or adjacent to, the textile apparatus to which yarn 22 is to bedelivered.

Affixed to support 224 by bolts 225 is a hollow housing 240 havingavertical opening 242 (FIGS. 13, 14) facing toward drive belt 220entrained about idler pulley 308. A vertical shaft 250 is supportedrotatably in the housing 240, and has a dependent portion 250 extendingbelow the housing. A drive wheel 286 is affixed to the upper portion ofshaft 250, inside shaft support 240, and is adapted to transmit rotationto the shaft when the peripheral surface of the wheel is in drivingcontact with drive belt 290, as shown in FIG. 13.

The lower portion 250 of shaft 250 supports the Sta-- tionary drum 226.The top of drum 226 is spaced from the bottom of the support or housing240 to provide clearance for mechanism to be described hereinafter inmore detail. The drum 226 includes a rotatable core 278 affixed to theouter races of spaced ball bearings 276 mounted on shaft portion 250',and a hollow housing 294 having its outer periphery formed as an annularbead 292 to provide the yarn rub rail.

The core 278 of drum 226 is formed with a plurality of vertical,peripherally spaced slots 280 in each of which is mounted a slidableflat bar or slat 282. Horizontal and vertical reciprocatory movementsare imparted to slats 282, for advancing the yarn turns on the drumaxially toward the discharge end thereof, by means of annular cams 268and 270. The bars 282 are formed with inner, vertical extensions oftheir top and bottom edges for reception of annular coil springs 273 toretain the slats at all times in contact with the cams 268, 270.

The cams 268 and 270 are secured to and concentric with the outer racesof ball bearings 272. The inner races of the ball bearings 272 aresecured angularly to hubs 269 keyed to shaft extension 250'. Both hubs269 are mounted eccentrically of shaft 250 (FIGS. 13, 16). The bearings272 are mounted in angular grooves in the hubs 269 so that cams 268, 270are angular, i.e., inclined, with respect to shaft portion 250'. Thus,as shaft 250 rotates, the annular cams 268, 270 are caused to wobblevertically in a cyclic, circular progression.

The outer periphery of cam 268 is beveled, while the outer periphery ofcam 270 is formed with a protruding lip 271 which engages snugly withincomplementary notches formed in the lower portions of the inner verticaledges of the slats 282 (FIG. 13). By reason of the eccentric mounting ofthe hubs 269, a horizontal reciprocatory motion is imparted by cams 268,270 to the slats 282 and, by reason of the wobbling motion of cams 268,270, a vertically reciprocatory movement is imparted to slats 282, whenshaft 250 rotates.

Affixed to the top of stationary drum 226 is a ring 360 formed with aplurality of uniformly spaced, circularly arranged, upstanding teeth.Similarly, affixed to the bottom of the support housing 240 is a ring361 having a plurality of uniformly spaced, circularly arranged,depending teeth. The tooth rings 360, 361 are concentric, are coaxialwith shaft 250, and have the same number of spaced teeth. Preferably,the bottoms of the spaces between the teeth are inclined outwardly toprevent the accumulation of foreign matter. The two rings of teeth 360,361 are spaced axially from each other, and their respective teeth aredisposed in opposing relation.

Keyed to the shaft 250, midway of the space between rings 360 and 361,is a hub 362. Angularly afi'ixed to hub 362 in the inner race of a ballbearing 364, whereby bearing 364 is inclined at an angle to the axis ofthe shaft 250. Affixed to the outer race of bearing 364, and co-planarwith said bearing, is a disc 365 having a plurality of uniformly spacedcircularly arranged, radial teeth 366 formed on its outer rim. The size,depth and spacing of the teeth 366 is such as to enable them to meshwith the teeth of the rings 360 and 361. Disc 365 comprises the novellocking means or key of this invention. The hub 362 and bearing 364together serve to suspend disc 365 angularly of the shaft 250.

By reason of the angular mounting of disc 365 on shaft 250, a verticalrhythmic wobbling motion is imparted to the disc as the shaft rotates.However, disc 365 does not rotate. The wobbling movement of disc 365 isprogressively undulating or cyclic, as shown by the shadow lines in FIG.13. The vertical spacing between the circularrows of teeth on rings 360iand 361 is such as to permit the teeth 366 of disc 365 to engagesimultaneously, at diametrically opposite locationsv of the disc, boththe teeth of ring 360.and those of ring 361. This inter-engagement ofthe teeth of disc 365 with the teeth of rings 360 and 361 operates toretain yarn collecting drum 266 stationary when shaft 250 rotates.

Thus, disc 365 acts as a detent or connector or wobble key to lock drum226 to the stationary housing or support 240 and thereby preventrotation of the drum. As shaft 250 rotates, causing disc 365 to wobblepregressively about the axis of the shaft, the teeth 366 of the discengage progressively, and mesh simultaneously with, the teeth of rings360 and 361, at diametrically opposite locations of the disc, thereby tolock the drum at all times to the stationary support or housing 240.

Keyed to shaft 250, for rotation therewith, just below the bottom ofhousing 240, is an outwardly extending, downwardly sloping yarn guidingarm 370. The yarn arm 370 extends outwardly of disc 365 and drum 226,and has at its distal end a vertically depending extension 371 whichterminates adjacent the periphery of drum 226 and supports yarn guide236. Yarn arm 370 is provided throughout its length with a bore 372, theouter end of which is provided with an opening 373.

It is to be noted (FIG. 13) that rotatable yarn arm 370 is disposedbetween upper toothed ring 361 and the toothed disc 365, and emergesfrom between the two above the lowest point of disc 365, where teeth 366are in engagement with the. upstanding teeth of lower ring 360. Thisrelationship between the parts is maintained at all times, since therotation of arm 370. is in unison with the cyclic wobbling motion ofdisc 365. Thus, the disc 365 functions to provide, at all times, arotatingopening for the yarn arm 370 extending from shaft 250, as shaft50 rotates;

The inner end of bore 372 of yarn arm 370 is in communication with avertical. slot 251 formed. in rotatable shaft 250. The slot 251 extendsfrom a location just below bore 372 upward of shaft 250 to the topthereof. The upper end of shaft 250 is counter-sunk and threaded toreceive a hollowthreaded nipple 375, serving as a yarn guide. Atransverse pin 376. is disposed in slot 251 immediately above the.location where the slot communicates with bore- 372 of yarn arm 370.

As shown in FIG. 13, the yam 22 which is to be stored temporarily ondrum 226 passes downwardly through nipple 375, through slot 251 in shaft250, around pin 376, then through bore 372 andv opening 373 to andthrough yarn guide 236 to drum 226. When belt 290 is brought intodriving'contact with wheel 286, yarn arm 370 is caused to revolve aboutdrum 226 to wrap the yarn about the drum. The result is to deliver theyarn tangentially to the drum for temporary storage thereon.

The pnuematic system of yarn tension equalizer 220 is generally similarto that of the'device 20 illustrated in FIG. 1. Support240 includes ahorizontal axis, cylindrical cavity 244 (FIG. 14) which serves as an airchamber. Cavity 244 is sealed at the top by a flexible diaphrarn 246,the latter being secured by means of a retaining ring 248 and threadedbolts 249. A piston 298 is axially slidable within air chamber 244, andring 248.

Diaphram 246 is interposed between the bottom of the piston and theinterior of the air chamber 244.

The pneumatic system includes a source of compressed air (not shown)which is connected to horizontal bore 258 in support housing 240. bymeans of air tubes 260 and 261 (FIG. 17). The bore 258 is interceptedaxially bya vertical bore 253, the upper portion of which iscounter-sunk and threaded. Bore 253 is adapted to receive an elongatedthreaded plug 254 having a transverse bore 255 generally axially alignedwith bore 258. Plug 254further includes an axial bore 256, the upper endof which is in communication with bore 255 and the lower end of whichterminates in orifice 262. O-ring 263provides an air tight seal betweenthe lower portion of plug 254 and vertical bore 253.

The bottom of vertical bore 253 is connected to the air cylinder 244 bymeans of reduced vertical bore 257 and horizontal bore 259. As is bestshown in FIG. 13, vertical. bore 257 is intercepted intermediate bores253 and 259 by horizontal bore 267. The latter is countersunk andthreaded to receive a threaded plug 265 having. an axial bore orelongated orifice 266. The cross sectional area of the bore or orifice266 preferably is at least three times larger than the cross sectionalarea of orifice 262 in plug 254. Orifice 266 is adapted to be closed. bya pivotal, vertically depending valve 264. Compressed air in the systemurges valve 264 to open position.

Thus, the yarn tension equalizer 220 illustrated in FIGS. 12-17incorporates a pneumatic system comprising a source of compressed air(not shown), an expansible air chamber 244 connected to said source,means comprising bores 259, 257, 267 and orifice 266 connecting the airchamber to the ambient atomsphere and a valve 264 for closing the airchamber to the atmosphere.

Mounted on the stationary support 240 is a vertically disposed yarnsensing finger 314 (FIG. 13). The upper end of finger 314 is pivoted at313, while its lower portion is in the general form of an inturned bow315. The latter is adapted to rest against the yarn turns on thestationary drum 226, after the yarn turns have advanced a pre-determineddistance downward of the drum. The position of finger 314, when restingon the yarn turns, is shown by the shadow lines 314A and 315A in FIG.13.

A spring 318 urges the yarn sensing means 314 in a clockwise. directionabout pivot 313, whereby its distal end 315 is urged toward theperiphery of the drum 226. When the number of yarn turns on drum 226 arereduced to a predetermined minimum, spring 318 forces finger 314inwardly in respect of drum 226, until a threaded screw 324, mounted onfinger 314, strikes valve 264 and causes the same to pivot to closeorifice 266, sealing air cylinder 244 from the atmosphere as shown inFIG. 13. As a result, compressed air no longer escapes from thepneumatic system to the atmosphere, and the air pressure in air chamber244 increases therein to advance piston 298.

The brakes used in device 20 of FIG. 1 are omitted from yarn tensionequalizer 220, and the linkage mechanism connecting piston 298 to idlerpulley 308 is simplified. Formed in the top of piston 298 is a slot 299(FIG. 12). Secured pivotally within piston slot 299, by pin 296, is oneend of a lever 300, the opposite end of which is formed with an upturnedportion 301. As best shown in FIGS. 13 and 14, lever 300 is mounted forpivotal movement about pin 306 secured in an extension of support 240.The upturned end 301 of lever 300 is bent into a horizontal support 302mounting a vertical stud shaft 303 for the rotatable idler pulley 308. Aspring 312 urges pulley 308 and lever 300 in a clockwise direction aboutpin 306, as viewed in FIG. 14, to retract belt 290 from wheel 286. Whenthe air pressure in air chamber 244 increases to advance piston 298, thepiston causes lever 300 and pulley 308 to pivot in the oppositedirection around pin 306. This brings belt 290 into driving contact withwheel 286, to impart rotary motion to shaft 250 and yarn arm 370 andcause a fresh supply of yarn 22 to be delivered to and wound upon drum226.

Thus, in response to the amount of air pressure in chamber 244,intermittent rotation is imparted to shaft 250 and yarn guide 236 bydrive belt 290 to provide at all times a temporary yarn store for theimmediate use of a yarn consuming apparatus. As in the case of thedevice of FIG. 1, yarn sensing finger 314 of the device 220 monitors theamount of yarn stored on the drum, so that when the number of yarn turnsare reduced to a minimum, the pneumatic system is activated to cause afresh supply of yarn to be wound on the drum. As the newly supplied yarnturns increase and advance axially downward of the drum, toward the yarndischarge end thereof, under the influence of slats 282, the yarn turnsforce sensing means 314 to pivot outwardly, to open valve 264 and permitreduction of the air pressure in air chamber 244. As the air pressurereduces in chamber 244, spring 312 causes pulley 308 and its drive belt290 to retract from wheel 286 while, at the same time, causing piston299 to retract into the air chamber.

As shown in FIG. 13, the device 220 preferably incorporates a stopmotion comprising a vertically pivotal sensing finger 234 adapted toswing inwardly to strike contact 235 mounted in drum core 278, in theevent of yarn breakage. Contact 235 is grounded through conductors 237and 241.

FIG. 18 illustrates schematically a modification of the pneumatic systemand retractable linkage means of device 220. Lever 300 extending fromthe piston 298' is pivoted about fixed pin 306, beyond pulley 308.Spring 312, therefore, urges drive belt 290' into driving relationshipwith wheel 286 while, at the same time, retracting piston 298 into theair chamber 244. When valve 264' on yarn sensing means 314 is closed,the air pressure builds up in the air chamber 244', to advance thepiston 298 and retract belt 290' from wheel 286. This halts the flow ofyarn to the drum.

In FIG. 19 there is shown schematically a pneumatic system slightlymodified from that shown in FIGS. 13, 14 and 17. In this instance, yarnsensing means 314" is pivoted at 316", and is formed with a right angledextension 317" pivotally connected to a link 319". The latter isconnected pivotally to a spool-like slidable valve 264" in bore 267" insupport 240". When the yarn sensing means 314" is in contact with theyarn turns, valve 264" is moved upwardly in bore 267 to seal the airchamber 244" from the source of compressed air (not shown) and to openthe chamber to the atmosphere. When the yarn turns are reduced to aminimum and yarn sensing means 314" caused to pivot toward the yarncollecting drum, valve 264" slides down bore 267", whereby the airchamber 244" is sealed from the atmosphere while, at the same time,placed in communication with the source of compressed air. As a result,compressed air flows through bore 257", valve 264" and bore 259" to airchamber 244". The increase in the air pressure in the chamber causespiston 298" to advance to bring belt 290 into driving contact with wheel286" and cause a fresh supply of yarn to be wrapped about the collectingdrum.

FIGS. 20, 21 and 22 illustrate schematically the use of the novel detentor locking means 365 of this invention for other textile machines. Thethree machines shown in FIGS. 20, 21 and 22 are all illustrated in theinverted or upside down position for the purpose of illustration.

In FIG. 20, there is disclosed a two-ply cord former having a rotatableshaft 400 mounted in stationary support 401 having a ring of uniformlyspaced teeth 402.

Shaft 400 passes through a drum 403 having a similar ring of uniformlyspaced teeth 404. The two rings of teeth 402, 404 are spacedsufficiently to permit the interposition therebetween of angularlydisposed disc 405 having a ring of uniformly spaced teeth 406 disposedabout its rim. In the manner previously explained, the disc or detent405, through the engagement of its teeth 406 with the teeth 402, 404,locks drum 403 to support 401 to prevent rotation of the drum.

A yarn package 408 is supported in drum 403 axially of shaft 400. Yarn409 is withdrawn from package 408 by means of a winder 410. A secondyarn 411 passes through a bore in shaft 400, thence through a bore inrotatable yarn arm 413 to the winder 410. The two yarns 409, 41 l, asthey are taken up by winder 410, are plied in the usual manner.

FIG. 21 illustrates the utilization of the angular, toothed disc ordetent in a conventional two-for-one twister having a rotatable shaft500 supported in stationary support 501 having a ring of uniformlyspaced teeth 502. Supported on rotatable shaft 500, and spaced fromsupport 501, is a drum 503 having a ring of uniformly spaced teeth 504.Rotation of drum 503 is prevented by the locking effect of the angularlydisposed disc or detent 505 having a ring of uniformly spaced teeth 506formed along its rim and engaging, respectively, with teeth 502 ofstationary support 501 and teeth 504 of drum 503.

Disposed axially of rotatable shaft 500 in drum 503 is a yarn package508 from which yarn 509 is withdrawn by means of a winder (not shown).Yarn 509 passes from the package 508 through a bore in shaft 500 andthence through a bore of the outwardly extending, rotatably yarn arm 513to the winder.

FIG. 22 shows a modified twister wherein the yarn 609 travels in theopposite direction from that of yarn 509 in FIG. 21. The machine of FIG.22 includes a rotatable shaft 600 mounted in stationary support 601having a ring of teeth 602. Disposed axially of shaft 600 and spacedfrom support 601 is a drum 603 having a ring of teeth 604. Disposedbetween the rings of teeth 602 and 604 is an angularly mounted disc ordetent 605 having a ring of teeth 606 formed about its rim andengagable, respectively, with the teeth 602, 604 to lock drum 603 tostationary support 601 to prevent rotation of the drum.

Rotatably mounted in drum 603 is a winder or other yarn take-up means610 connected by suitable gearing to rotatable shaft 600. Rotation ofwinder 610 draws yarn 609 from a yarn supply (not shown) through thebore of rotatable yarn arm 613 and thence through a bore in shaft 600 tobe formed into a suitable yarn package.

FIGS. 23 and 24 illustrate schematically yet another embodiment of thisinvention. In FIG. 23 there is shown a yarn source 700, such as a yarnextruder, from which the yarn must be drawn at a uniform and continuousrate, a yarn tension equalizer 701, having a stationary support 702 anda stationary drum 703, and a yarn consuming textile apparatus 705, suchas a winder. The toothed disc 704 disposed between support 702 and drum703 locks the latter against rotation.

In this embodiment, the drive belt 707 passing about pulley 708 ismaintained continuously in driving contact with wheel 709, to impartcontinuous, constant rotation to shaft 710 and yarn arm 711. Thus, theequalizer 701 draws yarn at a constant rate from extrud'er 700, anddelivers it to drum 703 for temporary storage en route to winder 705.

The pneumatic system for this modification is illustrated in FIG. 24,and includes a bore 714 in support 702 connected to a source ofcompressed air (not shown). Bore 714 bifurcates into bores 715 and 716in support 702. Bore 715 communicates with the atmosphere throughan-orifice in plug 717 which is adapted to be closed by valve 718mounted on the yarn sensing finger 719. Bore 716 leads to air chamber721, having mounted therein piston 722. Spaced ashort distance from theouter end of piston 722 is a microswitch 723 connected by electricalconduits 724 to a two speed electric motor 725 which drives the winder705.

In the event the yarn store on drum 703 should fall below a selectedminimum number of turns, the yarn sensing finger 719 is caused .to pivotinwardlyin respect of drum 703, to close valve 718 in the pneumaticsystem. Thiscauses the air pressure to rise in air chamber 721 toadvance piston 722 into contact with microswitch 723. Microswitch 723transmits anelectric signal through conduits 724 to motor 725, to slowdown the motor and reduce the rate at which yarn is 'withdrawn from drum703 by the winder. When a sufficient number of yarn turns have beenrestored to drum 703, the yarn turns cause yarn finger 719 to 'pivotoutwardly of the drum to open valve 718. Air pressure then is reduced inthe chamber 721 and the piston 722 permitted to retract from themicroswitch 723. This action transmits a new signal through conduits 724to the motor 725 to cause winder 705 to resume its former speed. Thus,the yarn sensing finger 719 and the pneumatic system of the yarn tensionequalizer 701 serve to slow down and speed up the'winder 705 in responseto the number of yarn turns on the drum 703, thereby maintaining at alltimes an ample store of yarn for delivery to the winder. I

Although certain preferred embodiments of this invention have been shownand described for purposes of illustration, it is to be understood thatthis invention may be applied to many other uses, and that variouschanges and modifications may be made therein without departing from thespirit and utility of the invention, or the scope thereof as set forthin the appended claims. A

I claim:

1. In an automatic yarn tension equalizer having a drum about which yarnis wound helically to form a plurality of turns and from which yarn isdrawn off in a generally axial direction at one end thereof, a yarnguide for delivering yarn to the drum, means for urging the yarn turnsaxially along the drum toward the yarn draw-off end of the drum andretractable drive means for rotating the drum and the yarn guiderelative to each other, means for advancing intermittently the drivemeans relative to the drum to cause the drum and the yarn guide .torotate relative to each other comprising:

a. a pneumatic system having 1. a source of compressed air,

2. an air chamber connected to the source of compressed air,

3. a valve for the air chamber and 4. means for opening and closing thevalve to vary air pressure in the chamber,

b. a piston slidably disposed within the air chamber and movable thereinin response to the amount of air pressure in the chamber,

c. yarn sensing means disposed adjacent the periphery of the drum forcollecting the valve, said sensing means being operative to 1. permitsaid valve to open to reduce air pressure in the air chamber when amaximum of yarn turns are on the drum and 2. permit said valve to closeto increase air pressure in the air chamber when a minimum of yarn turnsare on the drum, and

cl. retractable lever'mechanism connected to the piston and operative toadvance and retract the drive means in response to movements of thepiston.

2. In an automatic yarn tension equalizer having a drum about which yarnis wound to form a plurality of turns and from which yarn is drawn offat one end thereof, a yarn guide for delivering yarn to the drum anddrive means for rotating the drum and the yarn guide relative to eachother, means for engaging the drive means to cause the drum and yarnguide to rotate relative to each other comprising:

a. apneumatic system having 1. a source of compressed air,

2. an air chamber connected to the source of compressed air,

3. a valve for the air chamber and 4. means for opening and closing thevalve to vary air pressure in the chamber, b. a piston slidably disposedwithin the air chamber and movable therein in response to the amount ofair pressure in the chamber, c. yarn sensing means disposed adjacent theperiphery of the drum for controlling the valve, said sensing meansbeing operative to 1. permit said valve to open to reduce air pressurein the air chamber when a selected quantity of yarn turns are on thedrum and 2. permit said valve to close to increase air pressure in theair chamber when a second selected quantity of yarn turns are on thedrum, and

d. retractable lever mechanism connected to the piston and operative toengage and disengage the drive means in response to movements of thepiston. I

3. In an automatic yarn tension equalizer having a drum about which yarnis wound to form a plurality of turns and from which yarn is drawn offat one end thereof, a yam guide for delivering yarn to the drum anddrive means for rotating the drum and the yarn guide relative to eachother, means for engaging the drive means to cause the drum and the yarnguide to rotate relative to each other comprising:

a. a pneumatic system having l. a source of compressed air,

2. an air chamber connected to the source of compressed air,

3. a valve for the air chamber and 4. means for opening and closing thevalve to vary air pressure in the chamber,

b. yarn sensing means disposed adjacent the periphery of the drum andresponsive to the number of yarn turns on the drum for controlling thevalve, said sensing means causing said valve to open when a selectednumber of yarn turns are on the drum to reduce air pressure in thechamber, and

c. retractable linkage means operative to engage and disengage the drivemeans in response to the amount of air pressure in the chamber.

4. The yarn tension equalizer of claim 3, wherein the I drum isrotatable and the yarn guide is stationary.

5. The yarn tension equalizer of claim 4 further including:

a. a yarn sensing finger pivotally mounted on the drum,

b. resilient means operative to cause the finger to pivot outwardly ofthe drum when the yarn turns on the drum are reduced to a selectedminimum,

c. a lever connecting the finger to the valve and d. resilient meansoperative to urge the lever into valve closing position when the fingeris pivoted outwardly of the drum.

6. The yarn tension equalizer of claim wherein the drum is stationaryand the yarn guide is rotatable about the drum.

7. The yarn tension equalizer of claim 6 further including:

a. a yarn sensing finger pivotally mounted adjacent the drum,

b. resilient means operative to cause the finger to pivot inwardly ofthe drum when the yarn turns on the drum are reduced to a selectedminimum and 0. means on the finger operative to close the valve when thefinger is pivoted inwardly of the drum.

8. The yarn tension equalizer of claim 3 having:

a. a piston slidably mounted within said air chamber,

b. a lever mechanism connecting the piston to the drive means and c.resilient means connected to the lever mechanism operative to retractthe drive means when the valve is opened.

9. The yarn tension equalizer of claim 3 having:

a. a piston slidably mounted within said air chamber,

b. a lever mechanism connecting the piston to the drive means and c.resilient means connected to the lever mechanism operative to advancethe drive means when the valve is open.

10. The yarn tension equalizer of claim 3 wherein the drum has aplurality of arcuately spaced, axially extending slots formed therein,and includes slidable bars mounted in the slots and means to advance andretract the bars to advance the yarn turns toward the yarn drawofi endof the drum.

11. The yarn tension equalizer of claim 3 wherein the drive meansincludes:

a. a rotatable idler pulley mounted on the linkage means and b. a drivenbelt passing continuously around the pulc. the linkage means beingoperable to advance and retract the belt in response to the amount ofair pressure in the chamber.

12. The yarn tension equalizer of claim 3 wherein the pneumatic systemincludes:

a. a first orifice between the air chamber and the source of compressedair and b. a second orifice through which air is discharged from thechamber,

0. said second orifice having a cross sectional area larger than that ofthe first orifice and adopted to be opened and closed by the valve inresponse to the number of yarn turns on the drum.

13. The yarn tension equalizer of claim 3 further including means forconverting the same to a positive yarn feeding device, said meanscomprising:

a. linkage means for engaging the drive means to cause the drum and yarnguide to rotate continuously relative to each other and b. means forwithdrawing the yarn generally tangentially of the drum.

14. The yarn tension equalizer of claim 3 wherein the drum comprises aplurality of circularly arranged spaced rotatable rollers having axesinclined relative to the axis of the drum, and includes means to drivesaid rollers to advance the yarn turns toward the yarn drawoff end ofthe drum.

15. The yarn tension equalizer of claim 3 wherein the drum comprises aplurality of circularly arranged spaced endless belts, and includesmeans to drive said belts to advance the yarn turns toward the yarndrawoff end of the drum.

16. In a textile machine,

a. a shaft,

b. a support for the shaft,

c. a yarn passage in the shaft,

d. a drum mounted on the shaft and spaced from the e. a yarn arm fixedto and extending from the shaft between the support and the drum forguiding the yarn radially outward of the shaft,

f. means for advancing the yarn axially about the drum from the arm to apoint beyond the drum,

g. a detent mounted on the shaft and disposed between the support andthe drum for locking the drum to the support while providing an openingfor the yarn arm extending from the shaft and h. means for rotating theshaft and support relative to each other.

17. The machine of claim 16 wherein the shaft is rotatable and thesupport and the drum are stationary.

18. The machine of claim 16 wherein:

a. the detent comprises a disc having teeth engagable with teethdisposed on the support and teeth disposed on the durm, the teeth of thedetent, the drum and the support all being arranged circularly, and

b. the machine includes means for mounting the detent on the shaftangularly of the axis thereof, whereby the teeth of the detent engageprogressively the teeth of the drum and the teeth of the support atdiametrically opposed locations in the circle of teeth of the detent asthe shaft rotates relative to the support.

19. A yarn tension equalizer having:

1. In an automatic yarn tension equalizer having a drum about which yarnis wound helically to form a plurality of turns and from which yarn isdrawn off in a generally axial direction at one end thereof, a yarnguide for delivering yarn to the drum, means for urging the yarn turnsaxially along the drum toward the yarn draw-off end of the drum andretractable drive means for rotating the drum and the yarn guiderelative to each other, means for advancing intermittently the drivemeans relative to the drum to cause the drum and the yarn guide torotate relative to each other comprising: a. a pneumatic systemhaving
 1. a source of compressed air,
 2. an air chamber connected to thesource of compressed air,
 3. a valve for the air chamber and
 4. meansfor opening and closing the valve to vary air pressure in the chamber,b. a piston slidably disposed within the air chamber and movable thereinin response to the amount of air pressure in the chamber, c. yarnsensing means disposed adjacent the periphery of the drum for collectingthe valve, said sensing means being operative to
 1. permit said valve toopen to reduce air pressure in the air chamber when a maximum of yarnturns are on the drum and
 2. permit said valve to close to increase airpressure in the air chamber when a minimum of yarn turns are on thedrum, and d. retractable lever mechanism connected to the piston andoperative to advance and retract the drive means in response tomovements of the piston.
 2. an air chamber connected to the source ofcompressed air,
 2. permit said valve to close to increase air pressurein the air chamber when a minimum of yarn turns are on the drum, and d.retractable lever mechanism connected to the piston and operative toadvance and retract the drive means in response to movements of thepiston.
 2. In an automatic yarn tension equalizer having a drum aboutwhich yarn is wound to form a plurality of turns and from which yarn isdrawn off at one end thereof, a yarn guide for delivering yarn to thedrum and drive means for rotating the drum and the yarn guide relativeto each other, means for engaging the drive means to cause the drum andyarn guide to rotate relative to each other comprising: a. a pneumaticsystem having
 2. an air chamber connecteD to the source of compressedair,
 2. permit said valve to close to increase air pressure in the airchamber when a second selected quantity of yarn turns are on the drum,and d. retractable lever mechanism connected to the piston and operativeto engage and disengage the drive means in response to movements of thepiston.
 2. a yarn conduit fixed to and extending from the shaft to alocation radially outward of the drum, b. a lock for locking the drum tothe support, said lock comprising:
 2. locking means disposed on thesupport and on the drum for engaging the locking means of the disc c.and support means suspending the disc angularly of the shaft in lockingrelationship with the support and with the drum whereby, as the shaftand yarn conduit rotate, an angular undulating motion is imparted to thedisc to provide a rotating opening for the yarn conduit extending fromthe shaft.
 2. an air chamber connected to the source of compressed air,2. an air chamber connected to the source of compressed air,
 3. In anautomatic yarn tension equalizer having a drum about which yarn is woundto form a plurality of turns and from which yarn is drawn off at one endthereof, a yarn guide for delivering yarn to the drum and drive meansfor rotating the drum and the yarn guide relative to each other, meansfor engaging the drive means to cause the drum and the yarn guide torotate relative to each other comprising: a. a pneumatic system having3. a valve for the air chamber and
 3. a valve for the air chamber and 3.a valve for the air chamber and
 3. a valve for the air chamber and 4.means for opening and closing the valve to vary air pressure in thechamber, b. a piston slidably disposed within the air chamber andmovable therein in response to the amount of air pressure in thechamber, c. yarn sensing means disposed adjacent the periphery of thedrum for collecting the valve, said sensing means being operative to 4.means for opening and closing the valve to vary air pressure in thechamber, b. a piston slidably disposed within the air chamber andmovable therein in response to the amount of air pressure in thechamber, c. yarn sensing means disposed adjacent the periphery of thedrum for controlling the valve, said sensing means being operative to 4.means for opening and closing the valve, i. yarn sensing means disposedadjacent the periphery of the drum responsive to the number of yarnturns on the drum for controlling the means for opening and closing thevalve to vary air pressure in the chamber and j. retractable linkagemeans operative to engage intermittently the drive means with the shaftin response to the amount of air pressure in the chamber.
 4. The yarntension equalizer of claim 3, wherein the drum is rotatable and the yarnguide is stationary.
 4. means for opening and closing the valve to varyair pressure in the chamber, b. yarn sensing means disposed adjacent theperiphery of the drum and responsive to the number of yarn turns on thedrum for controlling the valve, said sensing means causing said valve toopen when a selected number of yarn turns are on the drum to reduce airpressure in the chamber, and c. retractable linkage means operative toengage and disengage the drive means in response to the amount of airpressure in the chamber.
 5. The yarn tension equalizer of claim 4further including: a. a yarn sensing finger pivotally mounted on thedrum, b. resilient means operative to cause the finger to pivotoutwardly of the drum when the yarn turns on the drum are reduced to aselected minimum, c. a lever connecting the finger to the valve and d.resilient means operative to urge the lever into valve closing positionwhen the finger is pivoted outwardly of the drum.
 6. The yarn tensionequalizer of claim 3 wherein the drum is stationary and the yarn guideis rotatable about the drum.
 7. The yarn tension equalizer of claim 6further including: a. a yarn sensing finger pivotally mounted adjacentthe drum, b. resilient means operative to cause the finger to pivotinwardly of the drum when the yarn turns on the drum are reduced to aselected minimum and c. means on the finger operative to close the valvewhen the finger is pivoted inwardly of the drum.
 8. The yarn tensionequalizer of claim 3 having: a. a piston slidably mounted within saidair chamber, b. a lever mechanism connecting the piston to the drivemeans and c. resilient means connected to the lever mechanism operativeto retract the drive means when the valve is opened.
 9. The yarn tensionequalizer of claim 3 having: a. a piston slidably mounted within saidair chamber, b. a lever mechanism connecting the piston to the drivemeans and c. resilient means connected to the lever mechanism operativeto advance the drive means when the valve is open.
 10. The yarn tensionequalizer of claim 3 wherein the drum has a plurality of arcuatelyspaced, axially extending slots formed therein, and includes slidablebars mounted in the slots and means to advance and retract the bars toadvance the yarn turns toward the yarn drawoff end of the drum.
 11. Theyarn tension equalizEr of claim 3 wherein the drive means includes: a. arotatable idler pulley mounted on the linkage means and b. a driven beltpassing continuously around the pulley, c. the linkage means beingoperable to advance and retract the belt in response to the amount ofair pressure in the chamber.
 12. The yarn tension equalizer of claim 3wherein the pneumatic system includes: a. a first orifice between theair chamber and the source of compressed air and b. a second orificethrough which air is discharged from the chamber, c. said second orificehaving a cross sectional area larger than that of the first orifice andadopted to be opened and closed by the valve in response to the numberof yarn turns on the drum.
 13. The yarn tension equalizer of claim 3further including means for converting the same to a positive yarnfeeding device, said means comprising: a. linkage means for engaging thedrive means to cause the drum and yarn guide to rotate continuouslyrelative to each other and b. means for withdrawing the yarn generallytangentially of the drum.
 14. The yarn tension equalizer of claim 3wherein the drum comprises a plurality of circularly arranged spacedrotatable rollers having axes inclined relative to the axis of the drum,and includes means to drive said rollers to advance the yarn turnstoward the yarn draw-off end of the drum.
 15. The yarn tension equalizerof claim 3 wherein the drum comprises a plurality of circularly arrangedspaced endless belts, and includes means to drive said belts to advancethe yarn turns toward the yarn draw-off end of the drum.
 16. In atextile machine, a. a shaft, b. a support for the shaft, c. a yarnpassage in the shaft, d. a drum mounted on the shaft and spaced from thesupport, e. a yarn arm fixed to and extending from the shaft between thesupport and the drum for guiding the yarn radially outward of the shaft,f. means for advancing the yarn axially about the drum from the arm to apoint beyond the drum, g. a detent mounted on the shaft and disposedbetween the support and the drum for locking the drum to the supportwhile providing an opening for the yarn arm extending from the shaft andh. means for rotating the shaft and support relative to each other. 17.The machine of claim 16 wherein the shaft is rotatable and the supportand the drum are stationary.
 18. The machine of claim 16 wherein: a. thedetent comprises a disc having teeth engagable with teeth disposed onthe support and teeth disposed on the durm, the teeth of the detent, thedrum and the support all being arranged circularly, and b. the machineincludes means for mounting the detent on the shaft angularly of theaxis thereof, whereby the teeth of the detent engage progressively theteeth of the drum and the teeth of the support at diametrically opposedlocations in the circle of teeth of the detent as the shaft rotatesrelative to the support.
 19. A yarn tension equalizer having: a. ashaft, b. a support for the shaft, c. drive means for rotating the shaftrelative to the support, d. a yarn passage in the shaft, e. a drummounted on the shaft and spaced from the support, f. a yarn arm fixed toand extending from the shaft between the support and the drum forguiding yarn radially outward of the shaft, g. a connector disposedbetween the support and the drum for locking the drum to the supportwhile providing an opening for the yarn arm as it rotates with the shaftrelative to the support, h. a pneumatic system having:
 20. The yarntension equalizer of claim 19 wherein: a. the connector comprises a dischaving teeth engagable with teeth disposed on the support and on thedrum and b. the equalizer includes means for mounting the disc on theshaft angularly of the axis thereof, whereby teeth of the disc engageprogressively teeth of the drum and teeth of the support at spacedlocations on the disc as the shaft rotates relative to the support. 21.The yarn tension equalizer of claim 19 wherein the shaft is rotatableand the support for the shaft is stationary.
 22. Yarn handling apparatushaving a. a rotatable shaft, b. a yarn passage in the shaft, c. astationary support for the shaft, d. a drum mounted on the shaft andspaced from the support, e. a yarn guide arm disposed between thesupport and the drum and affixed to the shaft for rotation therewith, f.said arm extending from the shaft to a point radially outward of thedrum, g. said arm having a yarn passage communicating with the yarnpassage in the shaft, h. a locking device in the space between thesupport and the drum, i. said locking device comprising a disc having acircle of teeth, j. a plurality of teeth on the support and on the drumand k. support means affixed to the shaft for mounting the discangularly of the axis of the shaft, to maintain the teeth of the discengaged with the teeth of the support and with the teeth of the drum atdiametrically spaced locations on the disc, to lock the drum to thesupport as the shaft rotates while maintaining an opening for the yarnguide arm.
 23. In yarn handling apparatus having a shaft, a support forthe shaft having a plurality of circularly-arranged teeth, a drummounted on the shaft and spaced from the support, said drum having aplurality of circularly-arranged teeth, a yarn guide extending from theshaft between the support and the drum for directing yarn generallyradially of the shaft and means for rotating the shaft and the supportrelative to each other, a. a locking device mounted on the shaft anddisposed between the support and the drum for locking the drum to thesupport while providing an opening for the yarn guide, b. said lockingdevice comprising a disc having peripheral teeth, and c. support meansaffixed to the shaft mounting the disc angularly of the axis of theshaft to maintain the teeth of the disc engaged with the teeth of thesupport and with the teeth of the drum at diametrically spaced locationson the disc to lock the drum to the support, while maintaining anopening for the yarn guide.
 24. The apparatus of claim 23 wherein a. theshaft is provided with an internal yarn passage and b. the yarn guidecomprises a yarn arm extending from the shaft and having a yarn passagecommunicating with the yarn passage in the shaft, c. said yarn armextending from the shaft to a point radially outward of the drum. 25.The apparatus of claim 24 wherein a. the shaft is rotatable and thesupport for the shaft is stationary and b. the yarn arm is fixed to theshaft for rotation therewith relative to the support.
 26. In textileapparatus having a rotatable shaft, a fixed support for the shaft and adrum mounted on the shaft and spaced from the support, a. yarn guidingmeans providing an uninterrupted yarn path extending from a locationinternally of the shaft to and externally of the drum to a locationspaced axially from the drum, said yarn guiding means including